Spiral antennas, generally characterized by a pair of dipole conductors which spiral inwardly from an outer portion of the antenna to an inner portion thereof, are well known in the prior art. Typically, the inner ends of each of the dipole conductors are disposed adjacent one another and are connected to an RF coaxial connector through a stripline balun assembly. This assembly includes a pair of opposed conductors disposed on a stripline, each of the opposed conductors being normally soldered in an independent manner to an associated one of the dipole conductors of the spiral antenna. In operation, an incident electromagnetic wave excites currents in the dipole conductors, contributing to an inward spiraling balanced electromagnetic wave. The balun serves to convert this balanced wave to an unbalanced coaxial TEM wave, and also transforms the impedance of the dipole conductors to match the characteristic impedance of the RF coaxial connector.
The use of "solder" joints between the stripline and the dipole conductors has proven to be a major cause of operational failure in spiral antenna design. Such joints are subjected to great stress during thermal and/or vibration testing. Also, these joints often fail during field service due to loads imposed by a coincident combination of thermal and vibratory influences, or from either of these singular influences. Such failure is caused by slight mechanical deflection of the dipole conductors. Another source of failure arises from contact/joint corrosion which occurs subsequent to initial assembly of the device. Such corrosion typically takes the form of an oxide build-up on and/or within the solder joint, precluding functional resistive contact.
There is therefore a need to provide an improved electrical connector for connecting a stripline to a spiral antenna which solves the problem of recurrent solder joint failure. Moreover, it is also desirable to obviate such solder joints generally, thus improving thermal compliance and preventing the corrosion normally associated therewith.